The burden of proof that is used in most civil cases which requires the party bearing the burden to prove something to make a showing that the the event more than likely happened. In theory, this burden is met if more than 50% of the evidence supports the finding.
California Jury Instruction No. 200. Obligation to Prove — More Likely True Than Not True:
“A party must persuade you, by evidence presented in court, that what he or she is required to prove is more likely to be true than not true. This is referred to as ‘the burden of proof.’
“After weighing all of the evidence, if you cannot decide that something is more likely to be true than not true, you must conclude that the party did not prove it. You should consider all the evidence, no matter which party produced the evidence.
“In criminal trials, the prosecution must prove that the defendant is guilty beyond a reasonable doubt. But in civil trials, such as this one, the party who is required to prove something need prove only that it is more likely to be true than not true.”